Decoupled, Closed-Loop, Multi-DoF Suspension of a Spherical Permanent Magnetic Dipole Actuator
Name
ASPE 2020 Final Paper Submission - ID 33 (Tyler Hamer).pdf
Size
5.37 MB
Format
Adobe PDF
Checksum (MD5)
955e1b600a7ce8b5f277609e2a3aad46
Author(s)
Hamer, Tyler Thomas
Chabot, Joshua
Trumper, David
Date Issued
December 2021
Publisher
American Society for Precision Engineering | Proceedings of the American Society for Precision Engineering 2020 Spring Topical Meeting on Design and Control of Precision Mechatronics Systems
Citation
T. T. Hamer, J. Chabot, and D. L. Trumper, “Decoupled, closed-loop, multi-DoF suspension of a spherical permanent magnetic dipole actuator,” in Proceedings of the American Society for Precision Engineering 2020 Spring Topical Meeting on Design and Control of Precision Mechatronics Systems, Cambridge, MA, USA. ASPE, 2020, pp. 31–36.
Version
Author's final manuscript
Abstract
This paper presents decoupled, closed-loop, multi-DoF (degree of freedom) suspension of a spherical, dipole permanent magnet used as the rotor in a reaction sphere bench-level prototype. Specifically, the reaction sphere’s rotor, a 38.1 mm (1.5 in) diameter, spherical NdFeB (Grade 42) permanent magnet (K&J Magnetics SX8), is suspended in all 3 translational DoFs by 12 equidistant cylindrical coils, one centered on each face of the surrounding dodecahedron stator. Due to symmetry of the rotor’s magnetic field and the coils’ layout, applied coil currents are commutated to apply force to the rotor without applying torque, decoupling translation from rotation such that the rotor’s position is controlled with minimal rotation induced. To properly commutate the coils, the rotor’s magnetization axis needs to be known. Twelve equidistant Hall Effect sensors (Allegro A1308KUA-1-T), each placed coaxially within a coil, measure the radial component of the rotor’s external magnetic flux density from which the rotor’s magnetization axis is estimated. The rotor’s angular velocity is also estimated from a backwards difference of the estimated rotor’s magnetization axis. The commutated coil currents are generated by three filtered proportional-integral-derivative (PID) controllers, one for each translation DoF, from an estimate of the rotor’s position, controlling the rotor’s position with a bandwidth of 60 Hz and a phase margin of 30°. Twelve equidistant reflective optical sensors (Fairchild QRE1113GR), each also placed coaxially within a coil, measure their distance from the rotor’s surface from which the rotor’s position is estimated.
Description
American Society for Precision Engineering 2020 Spring Topical Meeting on Design and Control of Precision Mechatronics Systems. 6-8 May 2020, online
Subjects
Spherical Motor
Spherical Actuator
Maglev Suspension
3-DoF Position Control
MIMO Position Control
Spherical Reaction Wheel
Terms of Use
Creative Commons Attribution-NonCommercial-ShareAlike
Persistent DSpace Link
DOI of Published Version
https://www.proceedings.com/61330.html
